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The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
The reaction of zinc with water is slowed by this passive layer. When this layer is corroded by acids such as hydrochloric acid and sulfuric acid, the reaction proceeds with the evolution of hydrogen gas. [1] [9] Zn + 2 H + → Zn 2+ + H 2. Zinc reacts with alkalis as with acids.
For example, comparing the potentials for zinc (-0.75 V) with those of iron (Fe(II) -0.47 V, Fe(III) -0.06 V) it is seen that iron ions are more easily reduced than zinc ions. This is the basis for using zinc to provide anodic protection for large structures made of iron or to protect small structures by galvanization.
Dilute hydrochloric acid can be used in place of dilute sulfuric acid. A replacement reaction where gaseous hydrogen chloride and fluorine gas react to release diatomic chlorine gas (because fluorine is more electronegative): + +
The Frankland-Duppa Reaction in which an oxalate ester (ROCOCOOR) reacts with an alkyl halide R'X, zinc and hydrochloric acid to form α-hydroxycarboxylic esters RR'COHCOOR [168] [169] Organozincs have similar reactivity to Grignard reagents but are much less nucleophilic, and they are expensive and difficult to handle.
The reaction is effected with zinc. The key zinc-intermediate formed is a carbenoid (iodomethyl)zinc iodide which reacts with alkenes to afford the cyclopropanated product. The rate of forming the active zinc species is increased via ultrasonication since the initial reaction occurs at the surface of the metal.
Zinc chloride is an inorganic chemical compound with the formula ZnCl 2 ·nH 2 O, with n ranging from 0 to 4.5, forming hydrates.Zinc chloride, anhydrous and its hydrates, are colorless or white crystalline solids, and are highly soluble in water.
Zinc smelting has historically been more difficult than the smelting of other metals, e.g. iron, because in contrast, zinc has a low boiling point. At temperatures typically used for smelting metals, zinc is a gas that will escape from a furnace with the flue gas and be lost, unless specific measures are taken to prevent it.